Airing Out Ice Dams? – Proper Ventilation for Better Winter Protection

If there’s one thing that you wouldn’t want on your roof during winter season, it’s ice dams. Ice dams are basically small pools of water from melted snow, trapped by frozen snow. Here’s a quick explanation of how these form on your roof.
ice dam roof

  1. Snow accumulates on your roof
  2. The surface of the roof, which is warmer than the snow itself, melts the ice directly over it
  3. Snow that isn’t partially melted by the roof’s warmth prevents the water from flowing to the gutter
  4. The trapped water has no choice but to seep through small gaps between shingles or panels

Most home owners focus on stopping ice dam formation right at the first step of the process. Unfortunately, this approach can be a very tedious and an ineffective process. Sure, you can always push snow off your roof, but ice dams can form as fast as a single evening. You could be spending an hour shoveling in the afternoon and wake up with ice dams the next morning. Some suggest using cable heaters, but these aren’t always effective and raise your monthly electric bill.

If you look at the ice dam process I listed earlier, you’ll notice that the main problem about ice dams – the melting snow – forms because of the warm roof surface. Preventing the roof surface from getting too warm is the key to keeping ice dams from developing, even if there’s a lot of snow on the roof. But how do you keep your roof from being too warm without you and your family freezing during the winter season?

You don’t have to give up comfort just to keep your roof free from ice dams. Keeping yourself warm is fine; the real problem starts when the warm air from your living room warms air trapped in the attic. This usually happens if your attic does not have a proper ventilation system. Imperial Building & Roofing Co recommends having a team come inspect your attic and the ventilation system to ensure everything is in order.

ventilation system

A proper ventilation system works in a few simple steps. Intake vents from lower parts of the roof let cold air inside the attic. Next, the cold air pushes the warm air out of the attic through a vent at the upper part of the roof. The warm air doesn’t stay long enough to warm up the roof, and the cold air also helps maintain the roof’s temperature. Because the roof stays cool enough, the snow directly in contact with the roof surface doesn’t melt, and ice dams won’t form.

ventilation system

The type of vent would depend on what kind of roof you have on your home. Most sloped roof designs usually do well with ridge vents, but gabled roofs also have the extra option of having gable vents. Low sloped and flat roof designs have a less distinct “top” area, and the warm air tends to spread more evenly, so you may have to get powered ventilation fans if you have that kind of roof.

Having proper ventilation plays a big role in preventing ice dam formation, but that doesn’t mean you should ignore other parts of the roof. As always, watch out for signs of roof problems on a regular basis, so you can prevent other winter roof problems and stay hassle free throughout the cold season.

About the Author:
John Zatwarnytsky is the Vice President of Homecraft, Inc. As one of the heads of the leading home contractors and roofers in Delaware, he sees to it that everything is in a smooth flow. He’s passionate about giving the best quality of service to his clients through the comfortable, energy efficient and beautifully done works. He reaches out to more people by trying to address common roofing and home improvement concerns through his blog.